The young transgender student, who calls herself "Aum Neko", was about to put one of the university's mottos _ "Thammasat has freedom in every square inch" - to the test again.
She had already stirred a beehive of criticism after a picture was posted online of Saran posing in a bikini in the campus cafeteria and another coyly perching on a statue of the father of democracy Pridi Banomyong, who is a revered historical figure at Thammasat.
But her latest campaign had a more serious message about the enforcement of wearing uniforms on campus and teaching students to conform to a conservative agenda. Saran argues that uniforms in Thai society are about re-enforcing the roles of elites and subordinates in Thai society.
The racy posters she put up at Thammasat's Rangsit campus carried provocative slogans such as: "Did you wear your uniform last mid-term test?"; "Does a uniform make sex better?"; and "Free your humanity".
"My campaign creates a chance for people who don't want to wear a university uniform," Saran said. "Many people misunderstand what we're trying to do. We're not trying to get rid of all uniforms in Thailand, such as those worn by soldiers, police, nurses and even school and university students.
''We won't force anyone to stop wearing a uniform if they feel appreciated and proud to wear it. We have no right to stop them and we can't change their thoughts. What we are doing is asking the university to accommodate a group that does not want to be controlled by the power of a uniform.''
The uniform rebellion was sparked earlier this month when the head of the science faculty, Pakorn Sermsuk, ordered that the wearing of uniforms by all science students in class be compulsory. He said science students needed to show they were disciplined individuals.
Saran and her fellow liberal arts students took it upon themselves to campaign for the rights of their science faculty cohorts, arguing their studies were being jeopardised.
She said that in the integrated social science and technology class, if you don't wear a uniform you are not given a test that is an important part of the assessment.
''If you don't wear a uniform for the whole period of studying, it means you are never involved in the class. They measure the value of student by a uniform.''
'A' IS FOR 'AGITATE
'The growing conservatism from the university hierarchy appeared to be spreading. At the Rangsit and Tha Phra Chan campuses of the faculty of commerce and accountancy, signs were hung by administration staff saying: ''No uniform, no service''.
Student web forums were alight with gossip that the university rector, Somkit Lertpaithoon, was steering Thammasat towards a more conservative agenda.
Prior to taking over as Thammasat rector in 2010, Mr Somkit was involved in the Constitution Drafting Assembly set up after the 2006 military coup that removed then prime minister Thaksin Shinawatra.
Mr Somkit also came under fire from the Pheu Thai Party in early 2012 when he forbade the Nitirat (Enlightened Jurists) group from holding a forum on constitutional reform on campus.
He argued that he did not want the university to be seen to be supporting any group and said he was concerned about violence on campus.
In the current dispute, Mr Somkit publicly insisted Thammasat students were not required to wear a uniform, although he said it was ''encouraged'' during exams and to show discipline in preparation for entering the workforce.
However, on his Facebook page he said he disagreed with the anti-uniform campaign and said the university's motto was being used by one person to do whatever they wanted at Thammasat. ''Those people have completely forgotten that helping people is the real ideology of the university,'' he wrote.
Mr Somkit was unavailable to speak to Spectrum.
NOT MY DEPARTMENT, SIR
Thammasat University student council has interviewed students and lecturers about the uniform debate and says they are divided over the issue.
Yukti Mookdawijit, an assistant professor in the faculty of social science, said he does not force his students to wear uniforms in class.
''It's their right to undertake the campaign as well as to choose what ever they want to wear,'' he said. ''They are not kids anymore. They can vote in a national election by law.''
Prapaipit Muthitacharoen from the faculty of journalism and mass communication was all in favour of uniforms but said she would never demand her students wear them.
''Personally, I think a uniform has its own benefit,'' she said. ''Not only for the university student but also for all occupations that require a uniform. It reminds them to realise their status and helps people understand their role in society while wearing a uniform.''
She said uniforms did not help control people, but instead made students more conscious of their responsibilities.
''The word control is quite negative. I think a uniform is something that makes students be more careful and think more before they do something. If they do not want to do something against the social norm, wearing a uniform should not be a problem.''
She added that while Thammasat was a place of freedom, students must respect their place in society.
Thammasat political science graduate Sanyakorn Singhaweratham, 24, said he disagreed with the younger generation and felt uniforms were appropriate for university students.
''The point of wearing a university uniform is to respect the place,'' said Sanyakorn, who is a reporter. ''I know that I can't change the minds of people who oppose uniforms. However, we have to differentiate between freedom and respect.''
The great uniform debate has sparked a humorous dialogue between both sides _ a nod to real liberalism, the ability not to take things too seriously.
Online fan pages dividing Thammasat into East and West have flowered, drawing comparisons with East and West Germany during the Cold War.
One fan page divides the university into the open red-coloured West, home to the liberal arts students, and the conservative East or blue-coloured science faculties where ''all living creatures, including animals'' are forced to wear uniforms. The map is completed with a neutral blue ''UN zone'' featuring bars, restaurants and entertainment areas.
The Central Intelligence Bureau of Thammasat joined in the fun, identifying a number of independence movements and new states.
Vanchai Tantiwitayapitak, a Thammasat alumnus and deputy director of Thai PBS said he does not attach much importance to the uniform debate.
''I think it's a joke,'' he said referring to the map.
''The problem is not about the uniform debate. The problem is that people in society at large are so divided. So when they see this debate bubbling up, they don't hesitate to expand on it and take a black-and-white stance on it.''
He said years of colour-coded national politics had prompted people to label others.
Last week Saran had a lese majeste complaint lodged against her by Phornthipa Supatnukul, director of the TV programme Best of Your Life.
Ms Phornthipa said she filed the case because she was angered by the student's behaviour.
The director said 20 Thammasat students were interviewed a couple of months ago about politics and economics and Saran had used the opportunity to allegedly criticise the royal institution.
Mr Vanchai said: ''Now, what I see is people who support the use of uniforms being labelled as conservative, and classifying those who oppose uniforms as being progressive.
''The real world is not that simple. It's not true that people from Thammasat's science side are all supportive of the uniform. The world is not black-and-white.''
The reporter Sanyakorn said there were more important issues for students and academics to worry about.
He cited the attempt by university students to help villagers fighting to have their voices heard during a public hearing about a gold mine in Loei as an example.
''Students from Khon Kaen and Rajabhat Maha Sarakham universities gathered to help local people ask the mining company to undertake am environmental health impact assessment,'' he said.
''They all wore their university uniforms and it did not seem like a uniform was a problem when it came to fighting for people.''